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Monica Ozores-Hampton, Philip A. Stansly, and Eugene McAvoy

. Tomato varieties/advanced breeding lines, seed sources, pruning, Tomato yellow leaf curl virus (TYLCV) symptomatic incidence and severity and bacterial leaf spot (BLS) severity during Spring 2007 and 2008 at Immokalee, FL. Cultural practices. Seed was

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Neel Kamal and Christopher S. Cramer

, S.K. Pappu, H.R. Schwartz, H.F. 2006 Iris yellow spot virus : An emerging threat to onion bulb and seed production Plant Dis. 90 1468 1480 Gent, D.H. Schwartz, H.F. Khosla, R. 2004 Distribution and incidence of Iris yellow spot virus in Colorado

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David G. Riley, Shimat V. Joseph, W. Terry Kelley, Steve Olson, and John Scott

TSWV-infected weed plants surrounding vegetable fields, acquire the virus, and move into tomato fields when planted ( Groves et al., 2001 , 2002 ). As thrips mature, the acquired virus replicates within the thrips and is readily transmitted, making

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Peter C. Andersen, Stephen M. Olson, M. Timur Momol, and Joshua H. Freeman

radiation ( Ham et al., 1993 ; Lamont, 2005 ; Tarara, 2000 ). Tomato spotted wilt is caused by a virus belonging in the genus Tospovirus and the family Bunyaviridae ( Adkins et al., 2009 ). TSW was originally described in Australia ( Brittlebank, 1919

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Joara Secchi Candian, Timothy Coolong, Bhabesh Dutta, Rajagopalbabu Srinivasan, Alton Sparks, Apurba Barman, and Andre Luiz Biscaia Ribeiro da Silva

. < > Nyoike, T.W. Liburd, O.E. Webb, S.E. 2008 Suppression of whiteflies, Bemisia tabaci (Hemiptera: Aleyrodidae), and incidence of cucurbit leaf crumple virus, a whitefly-transmitted virus of zucchini

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Katherine M. Solo, Sara B. Collins, Madalyn K. Shires, Ron Ochoa, Gary R. Bauchan, Liesel G. Schneider, Alan Henn, James C. Jacobi, Jean L. Williams-Woodward, M.R. Hajimorad, Frank A. Hale, John B. Wilkerson, Alan S. Windham, Kevin L. Ong, Mathews L. Paret, Xavier Martini, David H. Byrne, and Mark T. Windham

al., 2011 ). Upon return to the laboratory, RRD samples were stored at −20 °C until processed. Fig. 1. Map of the southern incidence line of Rose rosette virus (RRV) and eriophyid mites in Alabama, Georgia, and Mississippi in 2017. Plant hardiness

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Suzanne O’Connell, Cary Rivard, Mary M. Peet, Chris Harlow, and Frank Louws

tunnel exhibited less frequent TSWV compared with the field ( Fig. 6 , P < 0.05). In 2008, TSWV incidence was very low (less than 1% overall incidence) across both systems (data not shown). Fig. 6. Mean Tomato Spotted Wilt Virus (TSWV, Tospovirus

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George E. Boyhan, James E. Brown, Cynthia Channel-Butcher, and Virginia K. Perdue

A 3-year study to evaluate mulch type (reflective and black) and new virus resistant summer squash (Cucurbita pepo L.) varieties was undertaken. In the first year of the study (1996), in Shorter, Ala., under slight virus pressure, silver painted mulch suppressed virus symptoms through the final evaluation 2 months after planting. In addition, virus symptoms were significantly more prevalent on `Dixie' compared to `Supersett', `Tigress', `HMX 5727', `Jaguar', `Destiny III', and `Prelude II'. In the second year (1997), two different experiments were conducted in Savannah, Ga., where there was no virus pressure. In the first experiment at the Savannah location, `Tigress' and `HMX 6704' had significantly higher yields than `Destiny III', `Prelude II', `Puma', `Jaguar', `Meigs', `Dixie', and `Supersett'. In the second Savannah experiment, `Prelude II' and `Destiny III' had significantly higher yields than `Zucchini Elite', `Supersett', `HMX 6704', and `Jaguar'. In 1998 at Shorter, there was no difference in virus incidence based on mulch used. Although there were differences in virus incidence among varieties, the lowest incidence was 70% of plants infected for `Prelude II'. In addition to field evaluations, these varieties were evaluated for resistance to zucchini yellow mosaic virus under greenhouse conditions. Varieties HMX 7710, HMX 6704, Puma, Tigress, Prelude II, Jaguar, and Destiny III were significantly more resistant compared to varieties Zucchini Elite, Meigs, Supersett, and Dixie. In conclusion, reflective mulch was effective only under slight virus pressure.

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R. Precheur, C. Welty, R.M. Riedel, and M.R. Breth

Pumpkins rank third in acreage among Ohio's fresh market vegetables. Recently, increasing incidence of insect-vectored viruses have threatened the economic potential of this crop. Studies were initiated in 1992 to obtain information on abundance of insect pests, to evaluate the effect of insecticides, reflective mulch and row covers on pest density and yield of marketable fruit. In 1994 and 1995, statewide virus surveys were conducted to determine virus types infecting the pumpkin crop. In 1992 the greatest insect injury of concern was cucumber beetle feeding on fruit rinds, Insecticides lowered pest density, but there was no effect on marketable yield. In 1993, yield of virus-infected fruit was lower were reflective mulch was used than where rowcovers or foliar insecticides were used. Marketable yield and virus incidence in 1994 were not affected by reflective mulch, rowcovers or stylet oil due to the late arrival of the virus. In 1995, aphid infestations at three locations were significantly lower on plants on reflective mulch than on plants on bare ground. Results of the 1994 virus survey showed that watermelon mosaic virus (WMV) was the most common virus in Ohio pumpkins. The watermelon mosaic developed late in the season and fruit deformity was not severe enough to affect marketable yield. There was some incidence of cucumber mosaic and squash mosaic virus but zucchini yellow mosaic virus was not detected in 1994. Results of ELISA testing of samples collected in August/September 1995 at 27 farms were 18 farms positive for watermelon mosaic virus, 5 sites positive for squash mosaic, 4 sites positive for papaya ringspot and 1 site positive for zucchini yellow mosaic.

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J. Michele Myers, Philipp W. Simon, M.E.N. Fonseca, and Leonardo S. Boiteux

Garlic is an asexually propagated crop in which the greatest yield losses are attributed to virus infection. Currently, virus-free garlic is produced through shoot tip culture, and there are no known naturally occurring resistant clones. This study evaluated garlic germplasm (propagated from typical bulbs, not shoot tips) for incidence of two viruses known to infect garlic (onion yellow dwarf virus, OYDV and leek yellow stripe virus, LYSV) using dot blot ELISA. Young leaf tissue was collected from 173 garlic clones. For 118 clones, plants grown in the field from typical bulbs only were evaluated. For 55 clones, plants grown in the greenhouse from both bulbs and topsets (bulbils) were evaluated. Topsets are small bulbs that are produced in the inflorescence of stalking garlic. Each clone was tested at least three times for incidence of both viruses. In field grown bulbs, we found that 70% were infected with OYDV and 85 % were infected with LYSV. In greenhouse grown samples, incidence of OYDV was generally higher in plants from topsets than those from bulbs while no differences were seen for LYSV. Three clones were negative for both viruses and might be a useful source of resistance that can be used in producing virus resistant lines.